Leverage Java 17+ features for improved readability and performance

- Replace multi-line string concatenation with text blocks in HandlerMethod
- Use String.formatted() instead of string concatenation in exception messages
- Modernize string formatting using Java 17+ features

These improvements enhance code readability and leverage modern Java
capabilities while maintaining full backwards compatibility. All tests
pass successfully.

Closes gh-1320

Signed-off-by: jbj338033 <jbj338033@gmail.com>

Author: jbj338033

spring-graphql/src/main/java/org/springframework/graphql/data/method/HandlerMethod.java

@@ -365,10 +365,11 @@ protected String formatInvokeError(String text, @Nullable Object[] args) {
 				})
 				.collect(Collectors.joining(",\n", " ", " "));
 
-		return text + "\n" +
-				"Class [" + getBeanType().getName() + "]\n" +
-				"Method [" + getBridgedMethod().toGenericString() + "] " +
-				"with argument values:\n" + formattedArgs;
+		return """
+				%s
+				Class [%s]
+				Method [%s] with argument values:
+				%s""".formatted(text, getBeanType().getName(), getBridgedMethod().toGenericString(), formattedArgs);
 	}
 
 

spring-graphql/src/main/java/org/springframework/graphql/data/method/HandlerMethodArgumentResolverComposite.java

@@ -77,7 +77,7 @@ public boolean supportsParameter(MethodParameter parameter) {
 	public @Nullable Object resolveArgument(MethodParameter parameter, DataFetchingEnvironment environment) throws Exception {
 		HandlerMethodArgumentResolver resolver = getArgumentResolver(parameter);
 		if (resolver == null) {
-			throw new IllegalArgumentException("Unsupported parameter [" + parameter + "].");
+			throw new IllegalArgumentException("Unsupported parameter [%s].".formatted(parameter));
 		}
 		return resolver.resolveArgument(parameter, environment);
 	}

spring-graphql/src/main/java/org/springframework/graphql/server/support/GraphQlWebSocketMessageType.java

@@ -111,7 +111,7 @@ public static GraphQlWebSocketMessageType fromValue(String value) {
 				return type;
 			}
 		}
-		throw new IllegalArgumentException("No matching constant for [" + value + "]");
+		throw new IllegalArgumentException("No matching constant for [%s]".formatted(value));
 	}